Thermionic system



Oct. 9, 1934.

J. E. FOSTER 1,976,391

THERMIONIC SYSTEM Original Filed 1925 INVENTOR Patented Oct. 9, 1934 -I 1,976,391 THERMIONIC SYSTEM Julius Foster, Pittsburgh, Pa., assignor to Radio Corporation of America, a corporation of Delaware Original application January 8, 1925, Serial No. 1,182. Patent No. 1,864,591, dated June 28, 1932. Divided and this application June 5, 1929, Serial No. 368,685

12 Claims. (Cl. 25027) This invention relates in general to electronic In the usual rectifying circuits or syst the devices and to systems whereby such devices may positive and negative waves of an alternating curbe utilized to rectify. alternating currents, for rent are caused to assume the same cumulative generalapplication, but particularly for radio aprelationship whereby all of the current waves are plications where a, uniform or constant current, caused to traverse it predetermined load circuit 601 is desired. in the same direction, thereby establishing the The primary object of my invention is to pr effect of a direct current. Because of the spaced vide arectifying system and an electronic device relationship and the sinusoidal character oi the that may be suitably energized therefrom, by enne y effects of the W v w even w ergy derived from a source of alternating current both waves are rectified, the resultant current 65,.

such as the usual light and power circuit generally pr s nts a V y d r ct cu rent effect Sim lar to available. the super-imposition of an alternating current Another object of my invention is to provide up n a constant uniform direct current. an improved system for obtaining rectified c r- It is one of the objects of this invention to prorent of substantially uniform or constant values vide rectifying systems wherein the varying effect that may be suitable for application in radio cirin the resultant current is considerably dimincuits. o ished.

. In the parent application, Ser. No. 1,182, filed Rectification of alternating current is usually January 8, 1925, which has matured into Patent eifected by transmitting all Of the a o O No. 1,864,591 and of which this is a division, I polarity in succession thru a uni-directional curhave described an electronic device embodying a rent conducting medium. Due to their electrical rectifying unit of special construction whereby spacing such waves substantially constitute sucproper and complete rectification of an alter-v cessive spaced energy impulses. Between such nating current may be effected,toprovide a, source energy impulses of that polarity, no energy is 54 of substantially constant direct current or direct ordinarily. transmitted by the individual current current energy for the energization of a cathode conductin medium- W e t e Waves of both element in a 3-element tube. polarities, are rectified, the waves of the other The feature of importance that is involved in polarity are also transmitted through a uni-directhe construction of-that rectifier unit is that the tional current-conducting medium and combined filamentary electrodes of a double-wave rectifier with the wavesof the first polarity in a cumumust be properly arranged and separated, or lative sense. Since the energy impulses are alterisolated, to prevent current leakage between the nately transmitted, by the two conducting meactive zones around those filaments, if proper diums, however, and then combined in a single rectification of the alternating current is to be conducting medium, which is the load circuit, the obtained, and short circuiting of the associated space intervals between the energy impulses oi transformer is to be avoided. I i i one polarity are filled to a great extent by the Insofar as the teaching of the parent applicaenergy impulses of the other polarity. tion in that direction maybe applicable to the in- In order to provide a better rectification charventions disclosed herein, it is desired that such acteristic however, I modify the operation of each teaching be considered as apart of the present uni-directional current conducting medium in application. v such manner as to supplement the energy impulses The nature of the operation ofa radioreceivnormally transmitted by it. During the transing set, is such that small variations in energizing mission of. the normal impulse through the concurrent, or applied energy, are considerably magducting medium, an auxiliary energy impulse is nified. It is therefore desirable that the rectify-- stored in an auxiliary circuit. Duringthe noring system, whereby the usual available altermally inactive intervals between the normal nating-current energyis rectified to direct-curenergy impulses, the stored energy impulses are rent energy, shall be such as to reduce to a minisupplied to the load circuit. Since the normal mum the variation or ripple in the resultant energy impulses are transmitted by the two conrectified direct current, whichusually manifests ducting media or paths alternately, the accumuits p esence by the well known hum. If such relationof the normal and auxiliary energy imsultant energy can be maintained substantially pulses in the load circuit tends to establish a subconstant, any distortion that might be introduced stantially constant direct current effect. into the receiving circuit will be considerably The result of the ultimate rectified current -55jn,1inimiZcdmade up of the two substantially constant current 1 embodying impulses transmitted by each path is relatively free of variations and less likely to produce a humming effect.

In one modification of this invention I establish the storage of energy, during the normal transmission of a current energy impulse'through one conducting medium, by means of a condenser connected in shunt relation to the conducting medium. The terminals dium normally are the anode and the cathode of a. rectifying device. M I transmitted between the cathode and the anode,

energy is stored in the condenser. When the cir-" cuit polarity is such that current does not normally traverse the path betweenthe cathode and the anode, the condenser-discharges its stored energy into the load circuit to supplement the energy impulse already transmitted by the rectifier. The condenser thus transmits energy during the normally inactive periods of the rectii'ying medium. Since the two rectifying paths, that are ordinarily utilized to transmit the'respective current waves of each polarity, are similarly provided withauxiliary energy storage circuits, the combination of the transmitted normal impulses and the stored impulses provides a substantially constant uniform direct currentin the load circuit.- In another. modification of this invention described and claimed in another divisional application, which has matured into Patent No. 1,878,124, I utilize a plurality of filaments with each rectifying path, and connect a phase splitter between the energizing circuit. and the respective filaments of each rectifying path,- whereby each path will transmit a plurality. of overlapping wave impulses to provide a substantiallyconstant current transmission thru that rectifying path When each .of both usual rectifying paths is so provided with a phase splitter, which also serves as an energy storage system, the combined trans mitted currents. constitute a substantially con stant direct .currentavailable for the receiving circuit. The accompanying drawing illustrates... the modification in which the condensers. are utilizedas. the. energy-storage means associated wit'n the rectifying paths. v 7

Asis illustrated in the drawing, alternating cur-' rentv energy is. derived froma circuit 10, such as theusual light and power circuit, and is transformed to. the desired voltage by means of a transformer 11-, after which it is. rectified for use with a devicev illustrated herein asa combination elec tronic. device 12 divided intoa rectifying unit two rectifying chambers 13- and 14 respectively and. an amplifying unit 15. The rectifying unit 13 is. provided with .a filament or cathode l6. and a plate or anode 1,7.- The. rectifiying unitl l similarly comprises a filament I8: and a plate 19. The. filaments Iii/and 18. are.- respectively energized through the transformer 11 by two secondary windingsZl and. 22. One terminal. of each secondary winding is connected to. points.23;.and 24 on the. primary winding 25 spaced 'i from a mid-point 26 which serves. as an artificial.

neutral; point for the rectifyingsystem. Theamplifying chamber 15.contains1a filament- 3.0.,.a grid 31 and a plate 32. The filamentBtI is: connected. electrically between two. conductors.- connected to; the platesv 1'7 and-19;. respectively,.irr the rectifying units. Themid-point-of the filaa. mentSQ. is connected to the. artificial neutral; point 26 of the transformer thru; areactor 33; and; avariable resistor 34-. I

Betweenthe neutral point.26: and: the respect-2' of the conducting me:

tive terminals of the filament 30, which also substantially constitute the terminals of the anodes 17 and 19 in the rectifying units, are connected two condensers 35 and 36, respectively.

The connectionsxof the transformer 11 and the rectifying units are such that the rectifying units will be alternately efiective to transmit current.

.Each compartment will transmit only the current waves of one polarity. While the rectifying unit 13 is. transmitting its current wave or energy im- While current N is normally pulse, energy is stored in the condenser 35. When the polarity of the circuit conductors of the circuit 10 changes, the conducting path between the electrode 16 and the plate 17 transmits no energy to the filament 30. from the transformer. At the same time the change of polarity permits the energy stored in the condenser 35 to be supplied to the filament; The filament 30 thus receives the nQImal current impulse transmitted by the rectifying unit 13 at definite intervals corresponding to the frequency .of the energizing circuit 10, and, in between such intervals, receives the energy stored in the condenser 35.

The rectifying unit Hand its associated condenser 36. function similarly, so that the filament 3G is supplied with a substantially constant-cunrent made upofthecombination of energy impulses: transmitted by the rectifiers and the con densers. By reason of. the periodic reversal of: polarity of the energizing. circuit, the condensers are. alternately and periodically charged and dis charged. The reactor 33 is disposed in the com-' mon circuit and 'ser-vesas a stabil izer to diminish currentfiuctuati'on; i

The condensers 35 and 36 and the filament 39- 11:) of the amplifying unitthus constitute oscillating circuits that are periodically energized to supply substantially constant current to the filament 30, or load circuit; a e

My invention is: not limitedto "the specific details. of construction nor to the circuit connectionsthatare illustrated, but may be variously modified without: departing from thespiritand scope of the-invention as set forthin the appended'claims: I i 3 I'claim'as my invention:

1. In combination, a source 01 alternating cur rent, an audion provided with a filamentary cathode, a grid a plate, and means for segregating the-energy waves of opposites polarities and supplying all energy to the filamentary cath-- ode as unidirectional energy, andenergy-storing means'connected parallel relation 'to said seg regating means for supplying energy to the-cath odehduring 'the intervals when the segregatingm means are inactive 2: The method- 1 of:- energizing -a filamentary electrode of a vacuum tube from asouree of alternating current, which consists inseparately rectifying each halfwave of'thealternatmg curr35 rent and then supplying each separately rectified Wave'toa d ifEeren-tportion of the filamentary electrode? 7 3. In combination, an. audion having a filamentary cathode and means for controlling its 1A9 energiza'xtion, comprising a source of energy having a neutral point, two rectifiers energized fromsaid source and each having an anode connected to a terminal of the cathode, means connecting the m-id-point' of the cathode to the-neutralpoint 1:45 of the-source," and a condenser connected betw-eemeachend of' the cathode 'and'the" saidneutral point. 3 v

4. Incombination, an audioncomprising an= electron-emitting filamentary electrode;- and means for alternately energizing half portions of said electrode with directcurrent impulses derived from an alternating current source.

5. In combination, an audion comprising a pair of electron-emitting filamentary electrodes, and means for alternately energizing said electrodes with direct current impulses derived from an alternating current source.

6. In combination, an electron discharge device comprising a filamentary cathode, grid and plate electrodes, and means for energizing said cathode with rectified alternating current, comprising a source of alternating current, a pair of half-wave rectifiers energized from said source and each having included in its uni-directional current-conducting path one-half of the cathode.

'7. In combination, an electron discharge device comprising cathode, grid and plate electrodes, and means for energizing said cathode with rectified alternating current, comprising a source of alternating current, a pair of half-wave rectifiers alternately energized from said source and each having included in its uni-directional current-conducting path one-half of the cathode, and energy storing means connected between each end of the cathode and a low potential point common to both current conducting paths whereby the energy stored during the conducting periods will be discharged through its associated cathode portion during the non-conducting periods.

8. The combination with a radio tube having a filament, of two rectifiers mounted on the tube and connected with opposite ends of the filament, one rectifier being in series with one end of the filament and one being in series with the other end of the filament, and a terminal connected with the filament intermediate its ends.

9. The combination with a radio tube having a filament, of a pair of hot cathode rectifiers mounted on the tube and connected with opposite ends of the filament, one rectifier being in series with one end of the filament and one being in series with the other end of the filament, and a terminal connected with the filament intermediate its ends.

10. The combination with a radio tube having a filament, of rectifiers mounted on the tube connected with opposite ends of the filament, an alternating current source having a neutral point for energizing said rectifiers and a resistance connected between an intermediate point of the filament and the neutral point of the alternating current source.

11. The combination with a radio tube having a filament, of rectifiers mounted on the tube connected with opposite ends of the filament, an alternating current source having a, neutral point for energizing said rectifiers and an adjustable resistance connected between an intermediate point of the filament and the neutral point of 100 the alternating current source.

12. The combination of a radio tube having a filament, of rectifiers mounted on the tube connected with opposite ends of the filament, an alternating current source having a neutral point 105 for energizing said rectifiers and a conductor including a resistance and an inductance connected between an intermediate point of the filament and the neutral point of the alternating current source.

JULIUS E. FOSTER. 

